<!DOCTYPE html>
<html>
  <head>
    <meta charset="UTF-8">
    <title>Document</title>
  </head>
  <body>
    <script>
      console.log(Boolean(''));	    		// false
      console.log(Boolean(0));		    	// false
      console.log(Boolean(NaN));	  		// false
      console.log(Boolean(null));		  	// false
      console.log(Boolean(undefined));	// false
      console.log(Boolean('小白'));	  	// true
      console.log(Boolean(12));		    	// true
    </script>
  </body>
</html>